And plant ecology, or the study of relationships among plants, organisms, and their environments, is a huge field.

植物生态学——或者说研究植物、生物及其环境之间的关系——是一个巨大的领域。

Pond scum is the slang name for microalgae - green plant organisms, such as spirulina, which grow in water - like ponds and look a bit slimy or scummy before being dried.

绿藻是微藻的俗名，微藻是一种绿色的植物生物体，比如螺旋藻，它生长在像池塘这样的水里，在晒干之前看起来有点黏糊糊的。